Overview. Complex carbohydrates are made up of sugar molecules that are strung together in long, complex chains. Complex carbohydrates are found in foods such as peas, beans, whole grains, and vegetables.
Confidence votes 11.2K. Taught College level A&P for 27 years. The lens in the human eye is a convex lens, but it is flexible and when it is acted on by the ciliary muscle around it, the lens can be flattened to change the focus, or, when the muscle is relaxed, the lens can assume a more spherical shape.
A convex lens is thicker at the centre than at the edges. Convex lenses are thicker at the middle. Rays of light that pass through the lens are brought closer together (they converge). A convex lens is a converging lens. When parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus. The distance between the principal focus and the centre of the lens is called the focal length.